The maturity of electronic commerce and acceptance of the Internet as a daily tool by a continually growing user base intensify the need for communication engineers to design for scalability. The robustness of the global Internet stems in part from the routing protocols supporting such communication. The global Internet comprises largely a network of routers to direct network traffic. Improper routing results in packet loss and retransmissions. Namely, in a terrestrial setting, retransmissions do not impose a great cost in bandwidth, in view of the abundance of capacity afforded by advances in fiber optics and networking equipment. Bandwidth constraints are further heightened by the overhead cost of traditional routing protocols. As essentially a terrestrial system, the Internet can operate satisfactorily despite the inefficiencies of such routing protocols. By contrast, a satellite environment possesses unique characteristics compared to that of terrestrial systems, particularly with respect to bandwidth, latency, and network architecture. That is, in a satellite environment, capacity is relatively more precious such that protocol efficiency is a premium. Not surprisingly, bandwidth costs are significantly higher in a satellite network over a terrestrial system. In addition, the satellite network is burdened by inherent latencies stemming, for example, from propagation delay.
Architecturally, satellite systems exhibit interesting properties. These communication systems largely operate over the air according to a hub and spoke arrangement. Consequently,
Architecturally, satellite systems exhibit interesting properties. These communication systems largely operate over the air according to a hub and spoke arrangement. Consequently, many “neighboring” routing nodes potentially exist on the air side. Additionally, the connectivity over the air is relatively stable; i.e., there are few redundant routes, as most sites are expected to be stub sites.
Furthermore, new Internet applications follow a peer to peer computing model. Accordingly, an examination of the architecture of traditional satellite systems is required to support these peer to peer applications. The traditional hub and spoke approach would entail greater delay for such applications.
Based on the foregoing, there is a clear need for improved approaches for providing efficient routing over a relatively high latency network. There is also a need to routing support over an architecture that can accommodate emerging peer to peer applications.